FX1 is a base station/control station that operates through a repeater.
MO is mobile radios
FB is a base station that communicates with mobile radios.
Since you didn't include the call sign, I can't really tell you any more. Since this isn't a GMRS/FRS thing, unless it is a grandfathered license, it's kind of hard to guess what is going on.
DPL's do not have to be the same at both locations, and that may be to prevent interference between the two locations. The FCC does not assign DPL's, PL, page out tones, etc.
If you included the call sign, we could take a look and give you a hand...